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Calcium Crystals (calcium + crystal)
Selected AbstractsMetastatic pulmonary calcification in a dialysis patient: Case report and a reviewHEMODIALYSIS INTERNATIONAL, Issue S2 2006Christoph H. EGGERT Abstract A 19-year-old male presented with chest pain and dyspnea. He was anephric following nephrectomy for focal segmental glomerulosclerosis, had a subsequent failed transplant, and had been dialysis dependent for 3 years. Workup revealed hyperparathyroidism and an abnormal chest X-ray and computed tomography scan, significant for massive extra-skeletal pulmonary calcification. A markedly abnormal Technitium99 methylene diphosphonate (Tc99m-MDP) bone scan confirmed the clinical suspicion of metastatic pulmonary calcification. Metastatic pulmonary calcification (MPC) is common, occurring in 60% to 80% of dialysis patients on autopsy and bone scan series. It may lead to impaired oxygenation and restrictive lung disease. Typically, the calcium crystal is whitlockite rather than hydroxyapatite, which occurs in vascular calcification. Four major predisposing factors may contribute to MPC in dialysis patients. First, chronic acidosis leaches calcium from bone. Second, intermittent alkalosis favors deposition of calcium salts. Third, hyperparathyroidism tends to cause bone resorption and intracellular hypercalcemia. Finally, low glomerular filtration rate can cause hyperphosphatemia and an elevated calcium-phosphorus product. There may be other factors. Some authors suggest that the incidence of MPC in recent years may be lower due to improved dialysis techniques. The diagnosis is confirmed by biopsy, but can be suspected by typical findings on a Tc99m-MDP bone scan. Therapy is limited to ensuring adequate dialysis, correcting calcium-phosphorus product, and hyperparathyroidism; discontinuing vitamin D analogues may help. Conflicting reports show that transplantation may either improve or worsen the situation. MPC should be considered in dialysis patients who have characteristic abnormal chest radiography and/or pulmonary symptoms. [source] Tumoral Calcinosis of the Scalp: An Unusual Site for a Rare TumorTHE LARYNGOSCOPE, Issue 1 2007Jubbin Jagan Jacob MD Abstract Tumoral calcinosis is a rare calcifying disorder that is associated with deposition of calcium crystals in the periarticular tissues. The mass is most often around the hips, elbows, shoulders, and feet but may be occasionally found elsewhere. We report a case of multiple sporadic tumoral calcinoses in an adult male over the scalp. The scalp as a site of tumoral calcinosis has not been previously reported in adults. Previous surgical excisions done on two occasions had resulted in recurrence of the tumors. This report highlights the need to include tumoral calcinosis in the differential diagnosis of tumors of the scalp. [source] Calcification of articular cartilage in human osteoarthritisARTHRITIS & RHEUMATISM, Issue 9 2009M. Fuerst Objective Hypertrophic chondrocyte differentiation is a key step in endochondral ossification that produces basic calcium phosphates (BCPs). Although chondrocyte hypertrophy has been associated with osteoarthritis (OA), chondrocalcinosis has been considered an irregular event and linked mainly to calcium pyrophosphate dihydrate (CPPD) deposition. The aim of this study was to determine the prevalence and composition of calcium crystals in human OA and analyze their relationship to disease severity and markers of chondrocyte hypertrophy. Methods One hundred twenty patients with end-stage OA undergoing total knee replacement were prospectively evaluated. Cartilage calcification was studied by conventional x-ray radiography, digital-contact radiography (DCR), field-emission scanning electron microscopy (FE-SEM), and synovial fluid analysis. Cartilage calcification findings were correlated with scores of knee function as well as histologic changes and chondrocyte hypertrophy as analyzed in vitro. Results DCR revealed mineralization in all cartilage specimens. Its extent correlated significantly with the Hospital for Special Surgery knee score but not with age. FE-SEM analysis showed that BCPs, rather than CPPD, were the prominent minerals. On histologic analysis, it was observed that mineralization correlated with the expression of type X collagen, a marker of chondrocyte hypertrophy. Moreover, there was a strong correlation between the extent of mineralization in vivo and the ability of chondrocytes to produce BCPs in vitro. The induction of hypertrophy in healthy human chondrocytes resulted in a prominent mineralization of the extracellular matrix. Conclusion These results indicate that mineralization of articular cartilage by BCP is an indissociable process of OA and does not characterize a specific subset of the disease, which has important consequences in the development of therapeutic strategies for patients with OA. [source] A case of massive kidney graft calcification that developed early in a child recipient with hyperparathyroidismCLINICAL TRANSPLANTATION, Issue 2007Yukiko Kanetsuna Abstract:, A boy aged six yr and six months with end-stage renal disease because of focal segmental glomerulosclerosis underwent cadaveric renal transplantation. Ischemic injury during the operation resulted in a severely dysfunctional graft. A renal graft biopsy was performed on post-operative day (POD) 21. The biopsy specimen showed the presence of many intratubular calcium crystals, patchy tubular injury, and focal aggressive tubulointerstitial rejection. Pelvic computed tomography performed on POD 23 also showed prominent calcification in and around up to two-thirds of the graft. After the biopsy, the graft function recovered, and hemodialysis was stopped on POD 22. A second graft biopsy was performed on POD 52. This biopsy specimen showed recovery from rejection, although the nephrocalcinosis remained. It was suggested that secondary hyperparathyroidism and hyperphosphatemia provoked nephrocalcinosis in this patient. [source] | ||||||||||